Simulating FPGA Power Integrity Using S-Parameter Models

www.xilinx.com 1 © Copyright 2012 Xilinx, Inc. Xilinx, the Xilinx logo, Artix, ISE, Kintex, Spartan, Virtex, Zynq, and other designated brands included herein are trademarks of Xilinx in the United States and other countries. The purpose of a Power Distribution Network (PDN) is to provide power to electrical devices in a system. Each device in a system not only has its own power requirements for its internal operation, but also a requirement for the input voltage fluctuation of that power rail. For Xilinx KintexTM-7 and Virtex®-7 FPGAs, the analog power rails have an input voltage fluctuation requirement of not more than 10 mV peak-to-peak from the 10 kHz to the 80 MHz frequency range. The selfgenerated voltage fluctuation on the power rails is a function of frequency and can be described by Ohm's Law: Voltage (frequency) = Current (frequency) * Self-Impedance (frequency).